Overhead crane trolley turntable



April 13, 1954 B. M. QSOJNAK OVERHEAD CRANE TROLLEY TURNTABLE Filed Nov. 16, 1950 2 Sheets-Sheet 2' INVENTOR Bar/J M. 050 Jn 2k w 5 5 m mm.

Patented Apr. 13,}954 T OVERHEAD CRANE TROLLEY TURNTABLE Boris M. Osojnak, Pittsburgh, Pa., assignor to Heyl & Patterson, Inc., Pittsburgh, Pa., a corporation of Pennsylvania Application November 16, 1950, Serial No. 196,010

r 1 This invention relates to turntables for trolleys movable along overhead rails with means on the turntable for operating cables supporting a bucket or the like suspended beneath the trolley, the turntable being turnable on the trolley for rotating the suspended bucket or the like about a vertical axis.

A pair of independently driven cable drums are preferably mounted on such a trolley for the purpose of supporting and operating a bucket or the like, with one motor controlling the vertical movement of the bucket and the other motor acting or cooperating with the first motor to open and close the bucket or to tilt it between carrying and emptying positions. It has been customary to mount the motors for the drums on the same level as the drums in order to expose each drum and motor for servicing. When the motors and drums are mounted on the same level in the conventional manner the area occupied by these parts becomes extensive and it is not practicable to mount the drums and motors on a turntable because the large overhang beyond the rails causes interference with adjacent structures. As a result, it has heretofore been conventional to mount only a, single drum and motor on a turntable crane trolley, and this makes it more difiicult to operate the suspended bucket or the like than in the case where two cable drums with independently driven motors are used.

In accordance with the invention, the combined advantages of dual drums and motors and of a turntable for rotating the mechanism suspended beneath the trolley are achieved by suspending the trolley between the rails, mounting the turntable closely above the rails with only a slight overhang beyond the width of the rails, and mounting a pair of drums on opposite sides of and close to the turntable axis of rotation, with the motor for each drum mounted thereabove and also close to the axis of turntable rotation. In this way the center of gravity of the assembly on the turntable is brought as close as possible to the level of the rails, the moment of inertia of the assembly on the turntable is 4 Claims. (Cl- 212-21) to support the trolley or to prevent the trolley from overrunning its rails and falling on a ship or into the water below. The danger of overrunning may be appreciated when it is realized that such trolleys travel at a rate of about one thousand feet per minute and must be stopped at the end of a cantilever structure supporting the trolley over a ship at about ninety feet above Water level. The fact that the motors are mounted over the drums presents a problem in providing access to the drums, but in accordance with the invention this difiiculty is overcome by mounting each motor and drum on a multiple frame which has a plurality of separate sections which are normally secured together but which are readily disconnected to remove a motor with a portion of the driving gears to expose the drum therebeneath for repair or replacement. The various sections of the mounting are arranged to hold different halves of split bearing housings for the shafts of the geared drive between each motor and drum in order to facilitate the servicing or removal of the elements connected to the shafts, and the lowermost section is integral with the turntable to provide a strong but lightweight and easily fabricated construction.

Other details, objects and advantages of the invention will become apparent as the following description of a present preferred embodiment thereof proceeds. In the accompanying drawings I have shown, for purposes of illustration only, a present preferred embodiment of the invention, in which:

Figure 1 is a top elevation of a crane trolley incorporating my invention, resting on a brokenaway portion of a supporting railed bridge;

Figure 2 is a side elevation corresponding to Figure 1;

Figure 3 is an enlarged top elevation of a portion of the crane trolley;

Figure 4 is a side elevation corresponding to Figure 3; and Figure 5 is a partial section on the line V--V inFigure 4.

Referring now more particularly to the drawings and initially to Figures 1 and 2, a trolley [0 having a laterally travelling body H rests on a pair of spaced parallel rails l2 and i3 of a horizontal overhead bridge M with a conventional clam-shell bucket l5 suspended from the crane trolley beneath the rails. The trolley body ll extends between the rails l2 and i3, and axles l6 and H are journaled in upward extensions of the carriage ll adjacent its opposite ends.

Flanged wheels It on the axle l6 and flanged wheels I9 on the axle I! roll on the rails I2 and I3. Motors 20 and 2I on the trolley body II drive the wheels I8 and I9 respectively, and these wheels are controlled by brakes 22 on the rear extensions of the shafts of the motors 20 and 2I. Safety members 23 mounted on the four extreme corners of the trolley body II extend over the rails I2 and I3 to clear the rails for the wheels I8 and I9.

A horizontal turntable '24 having an outer railed ring 25 of slightly greater diameter than the width of the rails I2 and I3 is mounted closely above the rails I2 and I3 with its vertical axis centered therebetween. Four flanged wheels 26 are journaled in upwardly extending projections from the trolley body H, and the ring 25 is supported by and rolls on the wheels 25 about the central vertical axis of the turntable 24. The wheels 26 are distributed approximately equidistantly around the periphery of the ring 25 with two of the rollers close to the inner side of the rail I2 and the other two close to the inner side of the rail I3. Lateral movement of the ring 25 is normally opposed by the flanges of the wheels 26 or in emergency by a pair of flanged safety stops 2'! mounted on opposite sides of the ring 25 between the rails i2 and I3. The stops 21 extend over an outwardly flanged portion of the ring 25 in order to oppose tilting of the turntable '24, especially when the rate of movement of the trolley in either direction is being sharply changed. A motor 28 mounted on the trolley body II and controlled by a brake 29 drives the ring 25 through gearing 30 and a pinion 3| meshing with a toothed flange 32 around the ring 25.

A pair of parallel cable drums 33 and 34 are separately mounted on the turntable 25 on opposite sides of and close to the turntable axis of rotation and with their lower portions enclosed within the ring 25 close to the level of the rails I2 and I3. A set of cables 35 is Wound on the drum 33 and connected to the bucket I to move the bucket i5 vertically, and a second set of cables 33 are oppositely wound on the drum 3:5 and are connected to another portion of the bucket I5 in a conventional manner to open and close the bucket in cooperation with the cables 35. The drum 33 is driven by a motor 31 mounted thereabove and the drum 34 is independently driven by a motor 38. The motors 3? and 33 are also disposed close to the turntable axis of rotation.

The motor 31 has a motor shaft 45 having a front extension connected by a disconnectable coupling M to a shaft extension 42 on which is keyed a pinion 43. The rear extension of the motor shaft 40 is controlled by a brake M. A gear 45 keyed on shaft 45 is driven by the pinion 43, and a pinion ll keyed on the shaft 46 drives a gear 58 keyed on one end of a shaft 59 projecting axially and integrally from opposite ends of the drum 33.

The housing for the gearing between the drum 33 and motor 3'l is divided horizontally into three sections. The top section 56 mounts the upper halves of two spilt bearing housings over the shaft 42 on both sides of the pinion 43, and is detachably secured by bolts to a lower section 5| which mounts the other halves of said split bearing housings for the shaft 52. The section 5I also mounts the upper halves of two split bearing housings for the opposite ends of the shaft 46, and is detachably secured to another section 52 therebelow which mounts the other halves of the said bearing housings for the shaft 46. The section 52 also mounts the upper halves of two split bearing housings over the shaft 43 on both sides of the gear 45, and is detachably secured to a lowermost section 53 which mounts the other halves of the said split bearing housings for the shaft 49. The section 53 is constructed as an integral part of the turntable 2. The rear extension of the drum shaft 45 is journaled in a bearing 54 detachably secured to the turntable 24. A base 55 on which the motor 31 and its brake 44 are mounted has a lower extension at one endresting on and secured to the housing of the bearing 54, and at its other end is detachably secured to the intermediate section 52 of the gear housing. As a result, the motor 37 can be removed with its base 55 secured to the gear housing section 52 and the sections 55, 5I and 52 thereon to expose the drum 33 for repair or replacement.

The drum 34 and motor 33 are mounted in the same way for ready removal or servicing.

The motors are preferably all electric and are controlled from a cab 55 suspended beneath one end of the trolley body II (Figure 2). The bucket I5 is flexibly controlled by operating motors 25 and 2I to move the trolley body II in either direction along the rails I2 and I3 and thereby move the bucket laterally, by operating the motors 31 and 38 to raise and lower and to open and close the bucket, and by operating the motor 28 to rotate the turntable 24 and thereby revolve the bucket about its vertical axis. The close grouping of the heavy drums and motors on the turntable relative to the axis of rotation of the turntable reduces the rotational inertia and thereby enables a relatively small motor 23 to be used for operating the turntable. At the same time, the mass of the parts mounted on the turntable above the level of the supporting wheels 25 is kept as low as possible so that when the trolley is decelerated by the brakes 22 there is a minimum tendency of the turntable to tip in the direction of travel of the trolley. This is especially important when the bucket I5 is empty and hence there is the least amount of gravitational force holding the turntable assembly on the wheels 25.

While I have shown and described a present preferred embodiment of the invention it will be recognized that the invention is not limited thereto but may be otherwise variously embodied and practiced within the scope of the following claims.

I claim:

1. An overhead crane trolley turntable comprising a body, a plurality of adjacent hoist drums mounted on the body, each drum having a shaft extending therefrom, a plurality of independently operable motors mounted over the respective drums, a driving connection between each drum and its motor, a separate supporting frame for each motor straddling the corresponding drum and removably secured to the body, the body having halves of split bearing housings mounted therein in which the drum shafts are journaled, and the supporting frame for each motor having mounted therein the other halves of the split bearing housings in which the corresponding drum shaft is journaled, whereby each motor with its supporting frame can be lifted off of the drum therebelow to facilitate servicing the drums.

2. An overhead crane trolley turntable comprising a body, a plurality of adjacent hoist drums mounted on the body, a plurality of independently operable motors mounted over the respectlved rums, a driving connection between each drum and its motor, and a separate supporting frame for each motor straddling the corresponding drum and removably secured to the body, whereby each motor with its supporting frame can be lifted off of the drum therebelow to facilitate servicing the drums, the drums and motors being substantially entirely disposed within the horizontal confines of the body.

3. An overhead crane trolley turntable comprising a body, a plurality of hoist drums mounted on the body, a plurality of independently operable motors mounted o ver the respective drums, a driving connection between each drum and its motor, supporting means for each drum forming an integral part of the body and a separate supporting frame for each motor straddling the corresponding drum and removably secured to the supporting means for the drum therebelow, whereby the combined weight of the turntable structure and supporting means for the drums and motors is minimized and the drums are readily accessible for servicing, the drums and motors being substantially entirely disposed within the horizontal confines of the body.

4. An overhead crane trolley turntable comprising a body, a plurality of adjacent hoist drums a mounted on the body, a plurality of independently operable motors mounted over the respectiv drums, a driving connection between each drum and its motor and supporting frame means for the motors straddling the drums and removably secured to the body, whereby the motors with the supporting frame means therefor can be lifted off of the drums therebelow to facilitate'servicing the drums, the drums and motors being substantially entirely disposed within the horizontal confines of the body.

It references Cited in the file of this patent UNITED STATES PATENTS Number Name Date 866,247 Ward Sept. 17, 1907 994,004 Johnson May 30, 1911 1,148,323 Kendall July 27, 1915 1,670,733 Moore May 22, 1928 1,729,891 Moore Oct. 1, 1929 1,835,357 Townsend Dec. 8, 1931 2,366,558 Rauch Jan. 2, 1945 2,475,584 Baertschi July 12, 1949 2,553,378 Miller May 15, 1951 

